1 files changed, 700 insertions, 0 deletions

diff --git a/fs/xfs/xfs_dir2_readdir.c b/fs/xfs/xfs_dir2_readdir.c
new file mode 100644
index 00000000000..48e99afb9cb
--- /dev/null
+++ b/fs/xfs/xfs_dir2_readdir.c
@@ -0,0 +1,700 @@
+/*
+ * Copyright (c) 2000-2005 Silicon Graphics, Inc.
+ * Copyright (c) 2013 Red Hat, Inc.
+ * All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write the Free Software Foundation,
+ * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+#include "xfs.h"
+#include "xfs_fs.h"
+#include "xfs_format.h"
+#include "xfs_log_format.h"
+#include "xfs_trans_resv.h"
+#include "xfs_bit.h"
+#include "xfs_sb.h"
+#include "xfs_ag.h"
+#include "xfs_mount.h"
+#include "xfs_da_format.h"
+#include "xfs_da_btree.h"
+#include "xfs_inode.h"
+#include "xfs_dir2.h"
+#include "xfs_dir2_priv.h"
+#include "xfs_error.h"
+#include "xfs_trace.h"
+#include "xfs_bmap.h"
+#include "xfs_trans.h"
+#include "xfs_dinode.h"
+
+/*
+ * Directory file type support functions
+ */
+static unsigned char xfs_dir3_filetype_table[] = {
+	DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK,
+	DT_FIFO, DT_SOCK, DT_LNK, DT_WHT,
+};
+
+unsigned char
+xfs_dir3_get_dtype(
+	struct xfs_mount	*mp,
+	__uint8_t		filetype)
+{
+	if (!xfs_sb_version_hasftype(&mp->m_sb))
+		return DT_UNKNOWN;
+
+	if (filetype >= XFS_DIR3_FT_MAX)
+		return DT_UNKNOWN;
+
+	return xfs_dir3_filetype_table[filetype];
+}
+/*
+ * @mode, if set, indicates that the type field needs to be set up.
+ * This uses the transformation from file mode to DT_* as defined in linux/fs.h
+ * for file type specification. This will be propagated into the directory
+ * structure if appropriate for the given operation and filesystem config.
+ */
+const unsigned char xfs_mode_to_ftype[S_IFMT >> S_SHIFT] = {
+	[0]			= XFS_DIR3_FT_UNKNOWN,
+	[S_IFREG >> S_SHIFT]    = XFS_DIR3_FT_REG_FILE,
+	[S_IFDIR >> S_SHIFT]    = XFS_DIR3_FT_DIR,
+	[S_IFCHR >> S_SHIFT]    = XFS_DIR3_FT_CHRDEV,
+	[S_IFBLK >> S_SHIFT]    = XFS_DIR3_FT_BLKDEV,
+	[S_IFIFO >> S_SHIFT]    = XFS_DIR3_FT_FIFO,
+	[S_IFSOCK >> S_SHIFT]   = XFS_DIR3_FT_SOCK,
+	[S_IFLNK >> S_SHIFT]    = XFS_DIR3_FT_SYMLINK,
+};
+
+STATIC int
+xfs_dir2_sf_getdents(
+	struct xfs_da_args	*args,
+	struct dir_context	*ctx)
+{
+	int			i;		/* shortform entry number */
+	struct xfs_inode	*dp = args->dp;	/* incore directory inode */
+	xfs_dir2_dataptr_t	off;		/* current entry's offset */
+	xfs_dir2_sf_entry_t	*sfep;		/* shortform directory entry */
+	xfs_dir2_sf_hdr_t	*sfp;		/* shortform structure */
+	xfs_dir2_dataptr_t	dot_offset;
+	xfs_dir2_dataptr_t	dotdot_offset;
+	xfs_ino_t		ino;
+	struct xfs_da_geometry	*geo = args->geo;
+
+	ASSERT(dp->i_df.if_flags & XFS_IFINLINE);
+	/*
+	 * Give up if the directory is way too short.
+	 */
+	if (dp->i_d.di_size < offsetof(xfs_dir2_sf_hdr_t, parent)) {
+		ASSERT(XFS_FORCED_SHUTDOWN(dp->i_mount));
+		return XFS_ERROR(EIO);
+	}
+
+	ASSERT(dp->i_df.if_bytes == dp->i_d.di_size);
+	ASSERT(dp->i_df.if_u1.if_data != NULL);
+
+	sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
+
+	ASSERT(dp->i_d.di_size >= xfs_dir2_sf_hdr_size(sfp->i8count));
+
+	/*
+	 * If the block number in the offset is out of range, we're done.
+	 */
+	if (xfs_dir2_dataptr_to_db(geo, ctx->pos) > geo->datablk)
+		return 0;
+
+	/*
+	 * Precalculate offsets for . and .. as we will always need them.
+	 *
+	 * XXX(hch): the second argument is sometimes 0 and sometimes
+	 * geo->datablk
+	 */
+	dot_offset = xfs_dir2_db_off_to_dataptr(geo, geo->datablk,
+						dp->d_ops->data_dot_offset);
+	dotdot_offset = xfs_dir2_db_off_to_dataptr(geo, geo->datablk,
+						dp->d_ops->data_dotdot_offset);
+
+	/*
+	 * Put . entry unless we're starting past it.
+	 */
+	if (ctx->pos <= dot_offset) {
+		ctx->pos = dot_offset & 0x7fffffff;
+		if (!dir_emit(ctx, ".", 1, dp->i_ino, DT_DIR))
+			return 0;
+	}
+
+	/*
+	 * Put .. entry unless we're starting past it.
+	 */
+	if (ctx->pos <= dotdot_offset) {
+		ino = dp->d_ops->sf_get_parent_ino(sfp);
+		ctx->pos = dotdot_offset & 0x7fffffff;
+		if (!dir_emit(ctx, "..", 2, ino, DT_DIR))
+			return 0;
+	}
+
+	/*
+	 * Loop while there are more entries and put'ing works.
+	 */
+	sfep = xfs_dir2_sf_firstentry(sfp);
+	for (i = 0; i < sfp->count; i++) {
+		__uint8_t filetype;
+
+		off = xfs_dir2_db_off_to_dataptr(geo, geo->datablk,
+				xfs_dir2_sf_get_offset(sfep));
+
+		if (ctx->pos > off) {
+			sfep = dp->d_ops->sf_nextentry(sfp, sfep);
+			continue;
+		}
+
+		ino = dp->d_ops->sf_get_ino(sfp, sfep);
+		filetype = dp->d_ops->sf_get_ftype(sfep);
+		ctx->pos = off & 0x7fffffff;
+		if (!dir_emit(ctx, (char *)sfep->name, sfep->namelen, ino,
+			    xfs_dir3_get_dtype(dp->i_mount, filetype)))
+			return 0;
+		sfep = dp->d_ops->sf_nextentry(sfp, sfep);
+	}
+
+	ctx->pos = xfs_dir2_db_off_to_dataptr(geo, geo->datablk + 1, 0) &
+								0x7fffffff;
+	return 0;
+}
+
+/*
+ * Readdir for block directories.
+ */
+STATIC int
+xfs_dir2_block_getdents(
+	struct xfs_da_args	*args,
+	struct dir_context	*ctx)
+{
+	struct xfs_inode	*dp = args->dp;	/* incore directory inode */
+	xfs_dir2_data_hdr_t	*hdr;		/* block header */
+	struct xfs_buf		*bp;		/* buffer for block */
+	xfs_dir2_block_tail_t	*btp;		/* block tail */
+	xfs_dir2_data_entry_t	*dep;		/* block data entry */
+	xfs_dir2_data_unused_t	*dup;		/* block unused entry */
+	char			*endptr;	/* end of the data entries */
+	int			error;		/* error return value */
+	char			*ptr;		/* current data entry */
+	int			wantoff;	/* starting block offset */
+	xfs_off_t		cook;
+	struct xfs_da_geometry	*geo = args->geo;
+
+	/*
+	 * If the block number in the offset is out of range, we're done.
+	 */
+	if (xfs_dir2_dataptr_to_db(geo, ctx->pos) > geo->datablk)
+		return 0;
+
+	error = xfs_dir3_block_read(NULL, dp, &bp);
+	if (error)
+		return error;
+
+	/*
+	 * Extract the byte offset we start at from the seek pointer.
+	 * We'll skip entries before this.
+	 */
+	wantoff = xfs_dir2_dataptr_to_off(geo, ctx->pos);
+	hdr = bp->b_addr;
+	xfs_dir3_data_check(dp, bp);
+	/*
+	 * Set up values for the loop.
+	 */
+	btp = xfs_dir2_block_tail_p(geo, hdr);
+	ptr = (char *)dp->d_ops->data_entry_p(hdr);
+	endptr = (char *)xfs_dir2_block_leaf_p(btp);
+
+	/*
+	 * Loop over the data portion of the block.
+	 * Each object is a real entry (dep) or an unused one (dup).
+	 */
+	while (ptr < endptr) {
+		__uint8_t filetype;
+
+		dup = (xfs_dir2_data_unused_t *)ptr;
+		/*
+		 * Unused, skip it.
+		 */
+		if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
+			ptr += be16_to_cpu(dup->length);
+			continue;
+		}
+
+		dep = (xfs_dir2_data_entry_t *)ptr;
+
+		/*
+		 * Bump pointer for the next iteration.
+		 */
+		ptr += dp->d_ops->data_entsize(dep->namelen);
+		/*
+		 * The entry is before the desired starting point, skip it.
+		 */
+		if ((char *)dep - (char *)hdr < wantoff)
+			continue;
+
+		cook = xfs_dir2_db_off_to_dataptr(geo, geo->datablk,
+					    (char *)dep - (char *)hdr);
+
+		ctx->pos = cook & 0x7fffffff;
+		filetype = dp->d_ops->data_get_ftype(dep);
+		/*
+		 * If it didn't fit, set the final offset to here & return.
+		 */
+		if (!dir_emit(ctx, (char *)dep->name, dep->namelen,
+			    be64_to_cpu(dep->inumber),
+			    xfs_dir3_get_dtype(dp->i_mount, filetype))) {
+			xfs_trans_brelse(NULL, bp);
+			return 0;
+		}
+	}
+
+	/*
+	 * Reached the end of the block.
+	 * Set the offset to a non-existent block 1 and return.
+	 */
+	ctx->pos = xfs_dir2_db_off_to_dataptr(geo, geo->datablk + 1, 0) &
+								0x7fffffff;
+	xfs_trans_brelse(NULL, bp);
+	return 0;
+}
+
+struct xfs_dir2_leaf_map_info {
+	xfs_extlen_t	map_blocks;	/* number of fsbs in map */
+	xfs_dablk_t	map_off;	/* last mapped file offset */
+	int		map_size;	/* total entries in *map */
+	int		map_valid;	/* valid entries in *map */
+	int		nmap;		/* mappings to ask xfs_bmapi */
+	xfs_dir2_db_t	curdb;		/* db for current block */
+	int		ra_current;	/* number of read-ahead blks */
+	int		ra_index;	/* *map index for read-ahead */
+	int		ra_offset;	/* map entry offset for ra */
+	int		ra_want;	/* readahead count wanted */
+	struct xfs_bmbt_irec map[];	/* map vector for blocks */
+};
+
+STATIC int
+xfs_dir2_leaf_readbuf(
+	struct xfs_da_args	*args,
+	size_t			bufsize,
+	struct xfs_dir2_leaf_map_info *mip,
+	xfs_dir2_off_t		*curoff,
+	struct xfs_buf		**bpp)
+{
+	struct xfs_inode	*dp = args->dp;
+	struct xfs_buf		*bp = *bpp;
+	struct xfs_bmbt_irec	*map = mip->map;
+	struct blk_plug		plug;
+	int			error = 0;
+	int			length;
+	int			i;
+	int			j;
+	struct xfs_da_geometry	*geo = args->geo;
+
+	/*
+	 * If we have a buffer, we need to release it and
+	 * take it out of the mapping.
+	 */
+
+	if (bp) {
+		xfs_trans_brelse(NULL, bp);
+		bp = NULL;
+		mip->map_blocks -= geo->fsbcount;
+		/*
+		 * Loop to get rid of the extents for the
+		 * directory block.
+		 */
+		for (i = geo->fsbcount; i > 0; ) {
+			j = min_t(int, map->br_blockcount, i);
+			map->br_blockcount -= j;
+			map->br_startblock += j;
+			map->br_startoff += j;
+			/*
+			 * If mapping is done, pitch it from
+			 * the table.
+			 */
+			if (!map->br_blockcount && --mip->map_valid)
+				memmove(&map[0], &map[1],
+					sizeof(map[0]) * mip->map_valid);
+			i -= j;
+		}
+	}
+
+	/*
+	 * Recalculate the readahead blocks wanted.
+	 */
+	mip->ra_want = howmany(bufsize + geo->blksize, (1 << geo->fsblog)) - 1;
+	ASSERT(mip->ra_want >= 0);
+
+	/*
+	 * If we don't have as many as we want, and we haven't
+	 * run out of data blocks, get some more mappings.
+	 */
+	if (1 + mip->ra_want > mip->map_blocks &&
+	    mip->map_off < xfs_dir2_byte_to_da(geo, XFS_DIR2_LEAF_OFFSET)) {
+		/*
+		 * Get more bmaps, fill in after the ones
+		 * we already have in the table.
+		 */
+		mip->nmap = mip->map_size - mip->map_valid;
+		error = xfs_bmapi_read(dp, mip->map_off,
+				xfs_dir2_byte_to_da(geo, XFS_DIR2_LEAF_OFFSET) -
+								mip->map_off,
+				&map[mip->map_valid], &mip->nmap, 0);
+
+		/*
+		 * Don't know if we should ignore this or try to return an
+		 * error.  The trouble with returning errors is that readdir
+		 * will just stop without actually passing the error through.
+		 */
+		if (error)
+			goto out;	/* XXX */
+
+		/*
+		 * If we got all the mappings we asked for, set the final map
+		 * offset based on the last bmap value received.  Otherwise,
+		 * we've reached the end.
+		 */
+		if (mip->nmap == mip->map_size - mip->map_valid) {
+			i = mip->map_valid + mip->nmap - 1;
+			mip->map_off = map[i].br_startoff + map[i].br_blockcount;
+		} else
+			mip->map_off = xfs_dir2_byte_to_da(geo,
+							XFS_DIR2_LEAF_OFFSET);
+
+		/*
+		 * Look for holes in the mapping, and eliminate them.  Count up
+		 * the valid blocks.
+		 */
+		for (i = mip->map_valid; i < mip->map_valid + mip->nmap; ) {
+			if (map[i].br_startblock == HOLESTARTBLOCK) {
+				mip->nmap--;
+				length = mip->map_valid + mip->nmap - i;
+				if (length)
+					memmove(&map[i], &map[i + 1],
+						sizeof(map[i]) * length);
+			} else {
+				mip->map_blocks += map[i].br_blockcount;
+				i++;
+			}
+		}
+		mip->map_valid += mip->nmap;
+	}
+
+	/*
+	 * No valid mappings, so no more data blocks.
+	 */
+	if (!mip->map_valid) {
+		*curoff = xfs_dir2_da_to_byte(geo, mip->map_off);
+		goto out;
+	}
+
+	/*
+	 * Read the directory block starting at the first mapping.
+	 */
+	mip->curdb = xfs_dir2_da_to_db(geo, map->br_startoff);
+	error = xfs_dir3_data_read(NULL, dp, map->br_startoff,
+			map->br_blockcount >= geo->fsbcount ?
+			    XFS_FSB_TO_DADDR(dp->i_mount, map->br_startblock) :
+			    -1, &bp);
+	/*
+	 * Should just skip over the data block instead of giving up.
+	 */
+	if (error)
+		goto out;	/* XXX */
+
+	/*
+	 * Adjust the current amount of read-ahead: we just read a block that
+	 * was previously ra.
+	 */
+	if (mip->ra_current)
+		mip->ra_current -= geo->fsbcount;
+
+	/*
+	 * Do we need more readahead?
+	 */
+	blk_start_plug(&plug);
+	for (mip->ra_index = mip->ra_offset = i = 0;
+	     mip->ra_want > mip->ra_current && i < mip->map_blocks;
+	     i += geo->fsbcount) {
+		ASSERT(mip->ra_index < mip->map_valid);
+		/*
+		 * Read-ahead a contiguous directory block.
+		 */
+		if (i > mip->ra_current &&
+		    map[mip->ra_index].br_blockcount >= geo->fsbcount) {
+			xfs_dir3_data_readahead(dp,
+				map[mip->ra_index].br_startoff + mip->ra_offset,
+				XFS_FSB_TO_DADDR(dp->i_mount,
+					map[mip->ra_index].br_startblock +
+							mip->ra_offset));
+			mip->ra_current = i;
+		}
+
+		/*
+		 * Read-ahead a non-contiguous directory block.  This doesn't
+		 * use our mapping, but this is a very rare case.
+		 */
+		else if (i > mip->ra_current) {
+			xfs_dir3_data_readahead(dp,
+					map[mip->ra_index].br_startoff +
+							mip->ra_offset, -1);
+			mip->ra_current = i;
+		}
+
+		/*
+		 * Advance offset through the mapping table.
+		 */
+		for (j = 0; j < geo->fsbcount; j += length ) {
+			/*
+			 * The rest of this extent but not more than a dir
+			 * block.
+			 */
+			length = min_t(int, geo->fsbcount,
+					map[mip->ra_index].br_blockcount -
+							mip->ra_offset);
+			mip->ra_offset += length;
+
+			/*
+			 * Advance to the next mapping if this one is used up.
+			 */
+			if (mip->ra_offset == map[mip->ra_index].br_blockcount) {
+				mip->ra_offset = 0;
+				mip->ra_index++;
+			}
+		}
+	}
+	blk_finish_plug(&plug);
+
+out:
+	*bpp = bp;
+	return error;
+}
+
+/*
+ * Getdents (readdir) for leaf and node directories.
+ * This reads the data blocks only, so is the same for both forms.
+ */
+STATIC int
+xfs_dir2_leaf_getdents(
+	struct xfs_da_args	*args,
+	struct dir_context	*ctx,
+	size_t			bufsize)
+{
+	struct xfs_inode	*dp = args->dp;
+	struct xfs_buf		*bp = NULL;	/* data block buffer */
+	xfs_dir2_data_hdr_t	*hdr;		/* data block header */
+	xfs_dir2_data_entry_t	*dep;		/* data entry */
+	xfs_dir2_data_unused_t	*dup;		/* unused entry */
+	int			error = 0;	/* error return value */
+	int			length;		/* temporary length value */
+	int			byteoff;	/* offset in current block */
+	xfs_dir2_off_t		curoff;		/* current overall offset */
+	xfs_dir2_off_t		newoff;		/* new curoff after new blk */
+	char			*ptr = NULL;	/* pointer to current data */
+	struct xfs_dir2_leaf_map_info *map_info;
+	struct xfs_da_geometry	*geo = args->geo;
+
+	/*
+	 * If the offset is at or past the largest allowed value,
+	 * give up right away.
+	 */
+	if (ctx->pos >= XFS_DIR2_MAX_DATAPTR)
+		return 0;
+
+	/*
+	 * Set up to bmap a number of blocks based on the caller's
+	 * buffer size, the directory block size, and the filesystem
+	 * block size.
+	 */
+	length = howmany(bufsize + geo->blksize, (1 << geo->fsblog));
+	map_info = kmem_zalloc(offsetof(struct xfs_dir2_leaf_map_info, map) +
+				(length * sizeof(struct xfs_bmbt_irec)),
+			       KM_SLEEP | KM_NOFS);
+	map_info->map_size = length;
+
+	/*
+	 * Inside the loop we keep the main offset value as a byte offset
+	 * in the directory file.
+	 */
+	curoff = xfs_dir2_dataptr_to_byte(ctx->pos);
+
+	/*
+	 * Force this conversion through db so we truncate the offset
+	 * down to get the start of the data block.
+	 */
+	map_info->map_off = xfs_dir2_db_to_da(geo,
+					      xfs_dir2_byte_to_db(geo, curoff));
+
+	/*
+	 * Loop over directory entries until we reach the end offset.
+	 * Get more blocks and readahead as necessary.
+	 */
+	while (curoff < XFS_DIR2_LEAF_OFFSET) {
+		__uint8_t filetype;
+
+		/*
+		 * If we have no buffer, or we're off the end of the
+		 * current buffer, need to get another one.
+		 */
+		if (!bp || ptr >= (char *)bp->b_addr + geo->blksize) {
+
+			error = xfs_dir2_leaf_readbuf(args, bufsize, map_info,
+						      &curoff, &bp);
+			if (error || !map_info->map_valid)
+				break;
+
+			/*
+			 * Having done a read, we need to set a new offset.
+			 */
+			newoff = xfs_dir2_db_off_to_byte(geo,
+							 map_info->curdb, 0);
+			/*
+			 * Start of the current block.
+			 */
+			if (curoff < newoff)
+				curoff = newoff;
+			/*
+			 * Make sure we're in the right block.
+			 */
+			else if (curoff > newoff)
+				ASSERT(xfs_dir2_byte_to_db(geo, curoff) ==
+				       map_info->curdb);
+			hdr = bp->b_addr;
+			xfs_dir3_data_check(dp, bp);
+			/*
+			 * Find our position in the block.
+			 */
+			ptr = (char *)dp->d_ops->data_entry_p(hdr);
+			byteoff = xfs_dir2_byte_to_off(geo, curoff);
+			/*
+			 * Skip past the header.
+			 */
+			if (byteoff == 0)
+				curoff += dp->d_ops->data_entry_offset;
+			/*
+			 * Skip past entries until we reach our offset.
+			 */
+			else {
+				while ((char *)ptr - (char *)hdr < byteoff) {
+					dup = (xfs_dir2_data_unused_t *)ptr;
+
+					if (be16_to_cpu(dup->freetag)
+						  == XFS_DIR2_DATA_FREE_TAG) {
+
+						length = be16_to_cpu(dup->length);
+						ptr += length;
+						continue;
+					}
+					dep = (xfs_dir2_data_entry_t *)ptr;
+					length =
+					   dp->d_ops->data_entsize(dep->namelen);
+					ptr += length;
+				}
+				/*
+				 * Now set our real offset.
+				 */
+				curoff =
+					xfs_dir2_db_off_to_byte(geo,
+					    xfs_dir2_byte_to_db(geo, curoff),
+					    (char *)ptr - (char *)hdr);
+				if (ptr >= (char *)hdr + geo->blksize) {
+					continue;
+				}
+			}
+		}
+		/*
+		 * We have a pointer to an entry.
+		 * Is it a live one?
+		 */
+		dup = (xfs_dir2_data_unused_t *)ptr;
+		/*
+		 * No, it's unused, skip over it.
+		 */
+		if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
+			length = be16_to_cpu(dup->length);
+			ptr += length;
+			curoff += length;
+			continue;
+		}
+
+		dep = (xfs_dir2_data_entry_t *)ptr;
+		length = dp->d_ops->data_entsize(dep->namelen);
+		filetype = dp->d_ops->data_get_ftype(dep);
+
+		ctx->pos = xfs_dir2_byte_to_dataptr(curoff) & 0x7fffffff;
+		if (!dir_emit(ctx, (char *)dep->name, dep->namelen,
+			    be64_to_cpu(dep->inumber),
+			    xfs_dir3_get_dtype(dp->i_mount, filetype)))
+			break;
+
+		/*
+		 * Advance to next entry in the block.
+		 */
+		ptr += length;
+		curoff += length;
+		/* bufsize may have just been a guess; don't go negative */
+		bufsize = bufsize > length ? bufsize - length : 0;
+	}
+
+	/*
+	 * All done.  Set output offset value to current offset.
+	 */
+	if (curoff > xfs_dir2_dataptr_to_byte(XFS_DIR2_MAX_DATAPTR))
+		ctx->pos = XFS_DIR2_MAX_DATAPTR & 0x7fffffff;
+	else
+		ctx->pos = xfs_dir2_byte_to_dataptr(curoff) & 0x7fffffff;
+	kmem_free(map_info);
+	if (bp)
+		xfs_trans_brelse(NULL, bp);
+	return error;
+}
+
+/*
+ * Read a directory.
+ */
+int
+xfs_readdir(
+	struct xfs_inode	*dp,
+	struct dir_context	*ctx,
+	size_t			bufsize)
+{
+	struct xfs_da_args	args = { NULL };
+	int			rval;
+	int			v;
+	uint			lock_mode;
+
+	trace_xfs_readdir(dp);
+
+	if (XFS_FORCED_SHUTDOWN(dp->i_mount))
+		return XFS_ERROR(EIO);
+
+	ASSERT(S_ISDIR(dp->i_d.di_mode));
+	XFS_STATS_INC(xs_dir_getdents);
+
+	args.dp = dp;
+	args.geo = dp->i_mount->m_dir_geo;
+
+	lock_mode = xfs_ilock_data_map_shared(dp);
+	if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
+		rval = xfs_dir2_sf_getdents(&args, ctx);
+	else if ((rval = xfs_dir2_isblock(&args, &v)))
+		;
+	else if (v)
+		rval = xfs_dir2_block_getdents(&args, ctx);
+	else
+		rval = xfs_dir2_leaf_getdents(&args, ctx, bufsize);
+	xfs_iunlock(dp, lock_mode);
+
+	return rval;
+}